filling vs renewal

filling and renewal both are nouns.

Word	Noun	Adjective	Verb	Adverb
filling	Yes	No	No	No
renewal	Yes	No	No	No

As nouns, renewal is a hyponym of filling; that is, renewal is a word with a more specific, narrower meaning than filling:

Other hyponyms of filling include refilling, replacement, replenishment.

filling (noun)	renewal (noun)
the act of filling something	the conversion of wasteland into land suitable for use of habitation or cultivation
the yarn woven across the warp yarn in weaving	the act of renewing
(dentistry) a dental appliance consisting of any of various substances (as metal or plastic) inserted into a prepared cavity in a tooth	filling again by supplying what has been used up
a food mixture used to fill pastry or sandwiches etc.
flow into something (as a container)
any material that fills a space or container